12.1.3.6 Testsuite progress output

A custom test driver also has the task of displaying, on the standard
output, the test results as soon as they become available. Depending on
the protocol in use, it can also display the reasons for failures and
skips, and, more generally, any useful diagnostic output (but remember
that each line on the screen is precious, so that cluttering the screen
with overly verbose information is bad idea). The exact format of this
progress output is left up to the test driver; in fact, a custom test
driver might theoretically even decide not to do any such report,
leaving it all to the testsuite summary (that would be a very lousy idea,
of course, and serves only to illustrate the flexibility that is
granted here).

Remember that consistency is good; so, if possible, try to be consistent
with the output of the built-in Automake test drivers, providing a similar
“look & feel”. In particular, the testsuite progress output should be
colorized when the --color-tests is passed to the driver. On the
other end, if you are using a known and widespread test protocol with
well-established implementations, being consistent with those
implementations’ output might be a good idea too.